Next part of "A Review of Flight Dynamics and Numerical Analysis of an Unmanned Aerial Vehicle (UAV)" with case studies. Find previous presentation here- http://www.slideshare.net/HarshadaGurav/a-review-of-flight-dynamics-and-numerical-analysis-of-an-unmanned-aerial-vehicle-uav

1. A Seminar III
On
“Flight Dynamics and Numerical Analysis of an
Unmanned Aerial Vehicle (UAV)”
By
Ms. Harshada A Gurav
Guide
Prof. A. R. Suryavanshi
Department of Mechanical Engineering
Zeal Education Society’s
Zeal College of Engineering and Research, Pune.
Savitribai Phule, Pune University
[2015-16]

2. CONTENT
 Abstract
 Introduction
 Seminar II Review
 Case Study
 Summary
 References

3. ABSTRACT
Recent applications of an UAV requires good sustainability and
performance. Various types of mathematical simulation methods can
be adopted for analysis of UAV before actual production. The
simulation method can reduce the flight period, cost and risk. The case
studies are done for structural, vibration, fluid and landing analysis for
structural safety and performance. Maximum possible loads are
applied to observe and study extreme conditions. A total of 10 modal
frequencies are obtained for finding the resonant condition. The
landing analysis study kept limited to the stresses and deformation
calculations and fluid analysis is done to analyse the effect of air on
UAV in case of drag and pressure.

4.  An unmanned aerial vehicle (UAV), commonly known as
a drone, is an aircraft without a human pilot on board. Its
flight is either controlled autonomously by computers in
the vehicle, or under the remote control of a pilot on the
ground or in another vehicle. [1]

5. Review of Seminar II
Flight
Dynamics
Lift
Weight
Drag
Thrust
Blade
Flapping
Pitch
Roll
Yaw
Blade Flapping [9] UAV Movements [5,6] Forces acting on UAV [7,8]
Components of UAV [2] Flight Dynamics [4]

6. Review of Seminar II
TYPES
Size
Range
Altitude
No. of
rotors
Analysis
Static
Dynamic
Aerodyna-
mic
Crash and
Impact
Frequency
Types of UAV [3] Types of Analysis [10,11,12]

7. LITERATURE REVIEW
Sr.
No.
Title of Paper Author Summary
1 Structural Analysis of a Composite
Target-drone [1]
Yong-Bin Park
et al. [13]
Structural static and
dynamic analysis of a
wing and landing gear
2 Design and Structural Analysis for an
Autonomous UAV System Consisting of
Slave MAVs with Obstacle Detection
Capability Guided by a Master UAV
Using Swarm Control [2]
Lakshmi
Narashiman
Aswin et al.
[14]
Master and slave
frame structural
analysis.
3 Low Velocity Impact Analysis Of A
Composite Mini Unmanned Air Vehicle
During Belly Landing [3]
Serhan Yüksel
[3]
Studied impact
stresses induced
during belly landing
4 Design and aerodynamic analysis of a
flapping-wing micro aerial vehicle [4]
Bor-Jang Tsai
et al. [15]
Aerodynamic study
during different AOA
and K.
5 Design And Analysis of Engine
Mounting Frame of an UAV [5]
Santhosh N et
al. [16]
Frequency analysis of
frame.

8. CASE STUDY
 STRUCTURAL ANALYSIS
 Material - T7075-T6
(Aluminium Alloy)
 Density -2850 kg/m3,
 Yield Strength - 490 N/mm2
 Allowable Stress - 392 N/mm2
 Landing Gear Loads
 Lift Load = 1000 N
 Drag load = 450 N
 Side load = 260 N
 Torsion Load = 20000 N-mm [17]
Fig: CAD model of landing gear

9. Stresses and Deflection due to self weight
 Maximum von-mises stress of around 3.44 MPa is observed due
to self weight. This stress is much less the yield stress of the
structure. Also maximum deflection of 1mm due to self weight of
the landing gear is analysed at the wheel end.
Fig: Von-Mises stresses and deflection of landing gear under load

10. Stresses and Deflection due to loads
 Maximum von-mises stress is around 353 N/mm2 is observed
in the landing gear. The stress is less than the yield stress of the
material. Maximum displacement is around 22 mm (0.022 m).
Maximum displacement is taking place at the loading region.
Fig: Von-Mises stresses and deflection of landing gear due to self-weight

11. Set 1 2 3 4 5
Frequency (Hz) 15.6 98.3 104.5 130.2 177
Set 6 7 8 9 10
Frequency (Hz) 240 258 260 429 447
 VIBRATION ANALYSIS:
The frequency analysis is done for the same model used for
structural analysis. The modal frequencies are extracted for 10
frequencies. The modal frequencies are required to calculate
the resultant effect of modal spectrum vibration. The initial
frequency of 15.6 Hz is corresponding to a speed of 936 rpm.
This speed indicates resonance condition if the structure is
excited with 936 rpm of the air craft. [17]

12.  FLUID ANALYSIS
 Blended Wing Body (BWB)
aircraft is a concept where
fuselage is merged with wing
and tail to become a single entity
[18].
 Simulation is done for Mach
number 0.1 and 0.3
corresponding to Reynolds
number equals to 4.66 × 106 and
1.4 × 107 respectively.
 It is observed that the value of
CLmax increases as the air
velocity i.e. Reynolds number
Fig: CLmax versus Reynolds number
for wind tunnel experiments
CAD model of UiTM BWB-UAV

13. When the angle of attack α increases, the upper surface will
create a lower pressure coefficient, CP . For α = 0º, the high-
intensity blue area located on the upper surface suggests high
lift is generated with 7.4% force directed backward creating
drag. For α = 35º, BWB-UAV is still capable of generating lift,
however about 1/3 of the total force is directed backward (drag).
Fig: Pressure coefficient contours at α = 0º, M=0.3 and at α = 35º, M=0.3

14.  LANDING ANALYSIS
 The landing analysis for
Emperical Eagle Mini
UAV for belly landing is
done to analyze the
impact loads on the
composite sub-
structures [19].
 Composite material
used is carbon and
Kevlar fabric.
 The force equilibrium is assumed to be quasistatic in this case
for the impact velocity between 2 m/s to 10 m/s.
Fig: Belly landing Approach in Emperial Eagle
MINI UAV

15. Fig: Wing tip displacement
wrt. time in inclined drop
 In inclined drop analysis,
the wing displacement is
larger in initial time steps
then it decreases with
respect to time.
Fig: Maximum stress
plot Vs time in inclined
drop
 The maximum von-
Mises stress is
observed up to 118
MPa.

16. CONCLUSION
The study quadrotor dynamics, the review of literature for various
analyses is done. It can be said from the literature that, it is
essential to undergo through all types of analysis possible before
actual manufacturing of product. These all types of analysis are
studied including various case studies for structural analysis,
vibration analysis, fluid analysis and landing analysis. From these
case studies, it can be observed that, the stresses are produced
and it results in deflections which are negligible. Also from fluid
analysis it can be concluded that the given type of BWB can fly at
very high angle of attack. The resonance condition is found at 936
rpm with 15.6 Hz. and maximum stress of 118 MPa is observed in
landing analysis.

17. References
1. Louisa Brooke-Holland, “Overview of military drones used by the UK
armed forces”, House of Commons Library, Number 06493, 8 Oct. 2015,
pp. 1-54
2. J. Leishman, “Principles of Helicopter Aerodynamics”, Cambridge
University Press, New York, 2006.
3. Serhan Yüksel, “Low Velocity Impact Analysis of a Composite Mini
Unmanned Air Vehicle During Belly Landing”, Master Thesis, May2009,
Middle East Technical University.
4. Tommaso Bresciani, “Modelling, Identification and Control of a
Quadrotor Helicopter”, Master thesis, 2008, Lund University.
5. Guowei Cai, Ben M. Chen, Tong Heng Lee, “Unmanned Rotorcraft
Systems”, Advances in Industrial Control, Springer-Verlag London
Limited, 2011.
6. Ira H. Abbott, Albert E. Von Doenhoff, “Theory Of Wing Sections
Including A Summary of Airfoil Data”, Dover Publications, 1959.
7. Workbook, Naval Air Training Command, CNATRA P-401, 2013
8. Hoffman G. M., Huang H.; Waslander S. L; Tomlin C. J. "Quadrotor
Helicopter Flight Dynamics and Control: Theory and Experiment", In the
Conference of the American Institute of Aeronautics and Astronautics,
2007, pp: 1-20.

18. 9. Richard L. Burden, J. Douglas Faires, “Numerical Analysis”, Ninth Edition,
2011, Brooks/Cole, Cengage Learning.
10. Edward L. Wilson, “Three-Dimensional Static and Dynamic Analysis of
Structures”, Computers and Structures, Inc., Third Edition, January 2002
11. P. Yamuna, K. Sambasivarao, “Vibration Analysis of Beam With Varying
Crack Location”, International Journal of Engineering Research and
General Science, Volume 2, Issue 6, October-November 2014
12. Yong-Bin Park, Khanh-Hung Nguyen, Jin-HweKweon, Jin-Ho Choi, Jong-Su
Han, “Structural Analysis of a Composite Target-drone”, International
Journal of Aeronautical & Space Science, Vol. 12(1), 2011, pp. 84–91.
13. Lakshmi Narashiman Aswin, Prasanth Rajasekaran, Santhosh Kumar
Radhakrishnan, K. Shivarama Krishnan, “Design and Structural Analysis
for an Autonomous UAV System Consisting of Slave MAVs with Obstacle
Detection Capability Guided by a Master UAV Using Swarm Control”, IOSR
Journal of Electronics and Communication Engineering, 2013, Volume 6,
Issue 2, PP 01-10.
14. Bor-Jang Tsai, Yu-Chun Fu, “Design and aerodynamic analysis of a
flapping-wing micro aerial vehicle”, Aerospace Science and Technology,
Vol. 13, 2009, pp: 383–392.

19. 15. Santhosh N, Dr N D Shivakumar, Chetan D M, Pooja Kumari, Sahana B C,
Mahalya R, “Design And Analysis Of Engine Mounting Frame Of An
Unmanned Aerial Vehicle”, International Journal Of Research In
Aeronautical And Mechanical Engineering, Vol.2 Issue.5, 2014, pp: 27-35.
16. Mohammed Imran, Shabbir Ahmed. R. M, Dr. Mohamed Haneef, “Static
and Dynamic Response Analysis for Landing Gear of Test Air Crafts”,
International Journal of Innovative Research in Science, Engineering and
Technology, Vol. 3, Issue 5, May 2014, pp- 1-8
17. Wirachman Wisnoe, Rizal Effendy Mohd Nasir, Wahyu Kuntjoro, Aman
Mohd Ihsan Mamat, “Wind Tunnel Experiments and CFD Analysis of
Blended Wing Body (BWB) Unmanned Aerial Vehicle (UAV) at Mach 0.1
and Mach 0.3”, 13th International Conference on Aerospace Sciences &
Aviation Technology, May 26 – 28, 2009.
18. Akhilesh Kumar Jha, S. Sathyamoorthy, Bharath Kumar, Laxminarayank.,
“Impact Analysis of Mini UAV during Belly Landing”, DRDO Aeronautical
development establishment- Simulation Driven Innovation, 2012.

21. 1. Structural Analysis of a Composite Target-drone by Yong-Bin Park et al.
(2011) [10]
 H612 and WR580A glass fabric material is used for wing and Carbon fabric WSN3K is used
for landing gear.
Load
condition
Max. von-mises
stress (MPa)
Max. Deflection
(mm)
Max. Tsai-
Wu failure index
Buckling
load (N)
5g (2452 N) 168 82 0.930 2,380
-1.5g (736 N) 45 47 0.304 2,200
Tsai-Wu failure index for the main wing.
 The tip displacement deviation between the analysis and experimental results were 17%.
Deflections at wing tip

22. Landing angle
(deg)
Vertical landing
velocity (m/s)
Max. shear stress
(MPa)
0 1.4 7.8
15 5 61
30 10 959
Main landing gear dynamic analysis results
 Normal landing and landing with an angle of 15 degrees are safe.
 The max. Tsai-Wu failure index is 0.372
Tsai-Wu failure index for the main landing gear (Dynamic Analysis)
Back

23. 2. Design and Structural Analysis for an Autonomous UAV System
Consisting of Slave MAVs with Obstacle Detection Capability
Guided by a Master UAV Using Swarm Control by Lakshmi
Narashiman Aswin et al. (2013) [11]
 Master and Slave control theory where one UAV acts as a master while the others
act as slaves.
 For master quadrotor, maximum deformation takes place at the end of the
arms, where the motors are located.
 The displacements in master and slave MAVs are negligible.

24. Master Quadrotor Slave Birotor
Max. Deformation (mm) 0.0000296 0.00000215
Max. Stress (N/mm2) 0.0163 0.00039
Max. Reaction Forces (N) 0.409 0.0244
Displacement in master UAV Displacement in slave UAV
Back

25. 3. Low Velocity Impact Analysis Of A Composite Mini
Unmanned Air Vehicle During Belly Landing by Serhan
Yüksel (2009) [1]
 The objective of this study was to design a mini UAV that is tolerable to low
velocity impact loads.
 Fiber reinforced composite materials are used for strength and integrity.
 Velocity = 9 m/s, Safety factor = 4/3, approach angle= 3.5 degrees.
 Outer body modeling:
Maximum stress = 350 MPa (at the bottom of the fuselage).
 Internal structure modeling:
Maximum stress = 378.02 MPa (at internal layer of element at RHS)
Max. stress at the bottom of fuselage Max. stress at internal layer of right hand
side element

26. Internal structure modeling with wings:
Maximum stress = 700MPa (at Wing-fuselage junction )
 It can be concluded from the results that, cracks or fractures at that point
if necessary precautions are not taken.
Max. stress at the wing fuselage
junction
Belly Landing of “Güventürk”
Back

27. 4. Design and aerodynamic analysis of a flapping-
wing micro aerial vehicle by Bor-Jang Tsai et al.
(2009) [12]
 Objective is to analyse the flapping wing under different frequencies and
angles of attack.
 Flapping angle = 73 degrees, 8 g gross weight, the 15 cm wingspan, and 5
cm chord length.
Conceptual Design Meshing of wing

28. AOA ( ͦ ) CL CD Lift (g) Thrust (g)
0 0 − 0.018 0 0.4214
5 0.1875 − 0.0325 4.39 0.7609
10 0.3625 − 0.0775 8.4874 1.8146
The velocity vector diagram
of a flap cycle for K = 0.3,
AOA = 10◦, t/T = 3/6
It ranges from 0.00366 to
16.7 m/s
The lift and thrust force increases with increase in angle of attack.
Moderate increase in angle of attack is advantageous for
producing average lifting force and average thrust force.
Back

29. 5. Design And Analysis of Engine Mounting Frame Of
An UAV by Santhosh N et al. (2014) [13]
 Normal mode analysis is carried out in NISA II Software for 10
different mode shapes.
Mode No. 1 2 3 4 5
Frequency
(cycles/sec)
1.727722E+01 1.806157E+01 3.263030E+01 3.671007E+01 3.841202E+01
Mode No. 6 7 8 9 10
Frequency
(cycles/sec)
1.041444E+02 1.280067E+02 1.557057E+02 1.645914E+02 1.983670E+02
Frequency analysis of an UAV
frame – Mode shape plot for
mode no. 10.
Back